1. Field of the Invention
This invention relates to an electric automobile having fuel cell as its power source, and more particularly, to an arrangement of a fuel tank, a fuel reformer, a fuel cell and an electrical energy storage which constitute a fuel cell system.
2. Description of the Related Art
A fuel cell is well known in the art, and an electric automobile having a fuel cell as its power source is known from, for example, Japanese Patent Laid-Open Publication No. HEI-3-109126 or U.S. Pat. No. 5,641,031.
The fuel-cell-powered electric automobile disclosed in Japanese Patent Laid-Open Publication No. HEI-3-109126 is a small electric automobile for a very small number of passengers, such as two, and has a fuel cell mounted in the vicinity of the center of gravity of its body. This electric automobile has, however, a narrow space in its passenger compartment, since the reformer, fuel cell and other batteries are installed on the frame of its body and these devices are situated in its passenger compartment. This arrangement of devices is undesirable for an automobile for four or five or more passengers, since it has a narrow passenger compartment.
The fuel-cell-powered electric vehicle disclosed in U.S. Pat. No. 5,641,031 is of the type not having any electrical energy storage. According to one example, the reformer and fuel tank constituting the fuel cell system are installed within the loading compartment in the rear region of the vehicle, but this arrangement has the drawback of narrowing the loading compartment. Shown as another example is an electric vehicle having a fuel tank mounted in its front region, a reformer mounted in its rear region, and a fuel cell mounted between the fuel tank and the reformer. According to this other example, however, the interconnection of the devices requires complicated piping, and the arrangement of the devices does not provide any efficient flow through the fuel cell system, but needs improvement.
It is therefore an object of this invention to provide a fuel-cell-powered electric automobile for four or five or more passengers which makes it possible to realize an efficient arrangement of the components of its fuel cell system without narrowing the space in its passenger or loading compartment.
It is another object of this invention to provide a fuel-cell-powered electric automobile which makes it possible to realize an efficient arrangement of a distributor for distributing electric power generated by a fuel cell to an electrical energy storage and a motor in a fuel cell system, and an arrangement of its components which is beneficial for shortening their electrical wiring and simplifying the fabrication of the automobile including electrical wiring.
According to an aspect of this invention, there is provided a fuel-cell-powered electric automobile having a fuel cell as its power source, characterized in that a fuel tank, a fuel reformer, the fuel cell and an electrical energy storage are installed under its floor in their order as viewed longitudinally of its body.
According to this invention, therefore, the components of a fuel cell system including the fuel tank, reformer, fuel cell and electrical energy storage are arranged in the automobile body in accordance with progression through the system. Therefore, it is possible to shorten the piping and electrical wiring interconnecting the components, simplify the construction of the fuel-cell-powered electric automobile, facilitate its piping and wiring, and achieve an efficient arrangement of its fuel cell system.
Moreover, the components of the fuel cell system installed under the floor of the automobile body do not narrow the space in the automobile or its trunk compartment. Thus, the automobile and its trunk compartment have a broad space which is easy to use, and gives it an improved practical utility.
Moreover, the components of the fuel cell system are arranged longitudinally of the automobile in accordance with progression through the system. Therefore, the fuel cell and electrical energy storage which are greater in weight than the other components can be situated in the middle portion of the automobile, and the automobile has a good longitudinal balance of weight.
The electric automobile of this invention may further include a distributor installed in parallel to the electrical energy storage as viewed transversely of its body. Therefore, the electrical energy generated by the fuel cell can be supplied through the distributor to the motor in accordance with its load and to the electrical energy storage in accordance with the amount of energy stored therein. Moreover, the distributor is situated close to the electrical energy storage, and their electrical wiring can advantageously be shortened.
The automobile body has two longitudinally extending parallel frames which are appropriately spaced apart from each other along its width, and between which at least the reformer, fuel cell, electrical energy storage and distributor are installed.
Therefore, the frames protect the important components of the fuel cell system from any impact acting transversely upon the vehicle, and eliminate the necessity of providing any special protector for the fuel cell system or otherwise simplify the arrangement of such a protector.
A condenser is mounted on the top of the reformer for converting water vapor from the fuel cell to water. This arrangement allows water to enter the reformer by its own weight from the fuel cell, and eliminates the necessity of installing any special pump. etc. for supplying water to the reformer.